Need help, cant start car after engine replacement, master & hybrid warning icons, not "ready"

Hey all, just bought my 2nd (04) Prius, (I had a new '03 before). This one had an engine knock but ran fine, I found bearing pieces in the pan sump. Bought a used engine and replaced it, did not disturb the transaxle or hybrid components (aside from disconnecting the HV battery plug). After plugging both batteries in, I powered it on, it briefly flashed a master warning icon, then powered to the IG ON mode, engine did not try to crank, not showing "ready", no warning, trans would shift between neutral and park.
Checking the service books, I thought possibly the immobilizer was active, performed the reset procedure (remove aux batt negative while powered on & reconnect with keyfob still inserted). now I have a master warning & a hybrid warning icon on the MFD, trans is locked in park. Tried disconnecting both batts for half hour or so, still have the same result. I have rechecked and am certain all wiring, sensors, etc have been properly reconnected, engine turns freely by hand. HV batt was showing a little over half charged, aux batt is ok. I do not have the fancier required scanning tools, but my generic OBD II scanner does not show any DTC's (though it can only read the engine controller).

Has anyone run into this before & is there some sort of an initalizing process I need to perform after the batts have been off a while?

 

I did try reseating the plug, with the "latch bale" out 90*, I pushed it in and as it went in the lever rotated upward, then I locked it in, I believe that's the correct process...
The ECM is still original, I only replaced the bare long block engine.
I guess I can give the plug one more try though...Right now it's going to be a pain to get out of my shop & on a trailer being stuck in park...

 

Yeah, no joy on the plug...

 

How costly are the scanners?

 

Yes, I pushed it in, when it wouldnt push any farther (bale slightly out of straight up) I held in while latching it then gave it one more good push.

 

Jzchen, beleager all you want, stupid me was forgetting that last little slide downward after flipping the lever. The car now starts and sounds immensely better than it did before surgery. Thank you for that. What kept throwing me off was the "horizontal" last slide, mine is mounted so it slides downward on the last part.

 

lol I've had many of those nights, thanks again!